Arc-lamp.



A. SOHELLENBERGER.

'ARG LAMP.

11221.101111011 I'ILEDJULYZ was.

996,429; Patented June 27, 1911.

Witnefsses:

Inventor-z Albert schellenber ger, WM; 1411; MaQfi ms NORRIS PETERS co..wnsmuarou, 1:v c,

UNITED STATES PATENT OFFICE.

ALBERT SCHELLENBERGER, OF BERLIN, GERMANY, ASSIGNOR TO GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

ARC-LAMP.

To all whom it may concern:

Be it known that I, ALBERT SCHELLEN- BERGER, a subject of the King ofBavaria, residing at Berlin, Germany, have invented certain new anduseful Improvements in Arc-Lamps, of which the following is aspecification.

My invention has reference to improvements in are lamps with convergingelectrodes, and the object of the invention is to provide means whereby,when the electrodes have been consumed to a predetermined extent, thefurther maintenance of the arc will be interrupted, and whereby injuryto the lamp is prevented.

In the accompanying drawing, which forms a part of this specification,my invention is illustrated as follows:

Figure 1 is an elevation of a part of a lamp structure, partly insection, showing one form of my invention; and Fig. 2 is a like viewillustrating another form which my invention may assume.

Like numerals of reference indicate like parts.

In both figures of drawing, 1 represents the latform which ordinarilysupports the e ectromagnetic regulating mechanism, which is not hereshown, for the sake of simplicity. To the under side of this platformare secured, to lugs 2, two pairs of guide-bars 3, 3, one of each paironly being shown in the drawing, the others having been omitted for thesake of clearness. These guide-bars converge downwardly and they arefixed at their lower ends either to a lower platform, or to a bridge 4,as indicated with respect to one pair. Between these two pairs ofguide-bars extends a rail 6 from the center of which rises a post 7 towhich is joined the link 8 which freely passes through the platform 1and is understood to be connected with the electromagnetic regulatingmechanism of *the lamp which operates to lower the rail 6 as theelectrodes are gradually consumed. T 0 this rail is usually connected aweight 9, which serves as a counterweight for the regulating mechanism.The electrodes 10 and 11 we tend each between one pair of guide-bars 3;they are mounted in holders 12 and 13, re spectively, which are pivotedupon the axles of rollers 14, and either these axles or the holders 12and 18 are guided each between Specification of Letters Patent.

Application filed July 2, 1908.

Patented J une 27, 1911.

Serial No. 441,598.

one pair of guidebars 3. The rollers 14 rest upon the rail 6, asindicated. The lower end of the electrode 10 passes through the lowerplatform or bridge 4, while the electrode 11 passes through plate 5which is laterally adjustable. It is adjusted by a bell-crank lever 15pivoted to a standard 16, and one arm of the bell-crank lever is c011-nected by a link 17 with the electromagnetic regulating mechanism. Thisconnection, however, is not shown in the drawing, since suchillustration is unnecessary for the understanding of my invention. Theother arm of the bell-crank lever is bifurcated, as shown, and extendsinto a slot 18 in the movable plate 5 and there embraces a pin 19 whichpasses transversely through that slot.

The operation of alamp of this kind is well understood in the art. Theare is struck by the separation of the electrode 11 from the electrode10 by the rocking of the bell-crank lever 15 caused by a downwardmovement of the link 17 which in turn is actuated by the electromagneticdevices un derstood to be mounted above the platform 1. This conditionis shown in the drawing.

As the electrodes are gradually consumed, the arc becomes longer and theregulating mechanism tends to lift the link 17 and thereby move thebell-crank lever to cause a nearer approach of the electrode 11 to theelectrode 10. After a while the lengthening of the arc cannot becompensated for by this part of the regulating mechanism, and thenanother part of the regulating mechanism lowers the rail 6, whereby bothelectrodes are fed downwardly and thus shorten the arc to its normallength. All this is familiar and is understood by those skilled in theart. But if the electrodes are permitted to thus feed downwardly untilthe rail 6 has reached the end of its downward travel, and if in thisposition the electrodes were allowed to consume and approach each othermore and more by the action of the regulating mechanism on thebell-crank lever, the arc would come dangerously near either the lowerplatform or bridge 4, or to any economizer that might, as is ordinarilythe case, be used in that location. and either the platform or bridge 4,or the economizer, or both, would be burned out or fused by the arc.This is actually what happens in lamps of this general character, and myinvention is directed toward the prevention of this trouble. For thispurpose I provide means for locking the bell-crank lever againstmovement that would shorten the are after the rail 6 and with it theelectrodes have been fed down to their lowermost point. In theconstruction shown in Fig. l the means for preventing the lateralfeeding action of the bell-crank lever consists of a pin or rod 20secured to and projecting downwardly from the rail (3, and in suchposition that by the time the rail has been fed down to its lowermostposition the rod 20 strikes against a lateral extension 15 of thebellcrank lever. This is indicated in dotted lines in Fig. 1, and itwill now be readily understood that as soon as the relation of partsthus indicated has been reached the link 17, impelled by theelectromagnetic regulating mechanism, or, for that matter, in any otherWay, cannot any more rock the bell-crank lever so as to approach theelectrode 11 to the electrode 10. Consequently, the arc cannot beshortened, and it will, therefore, lengthen and finally break before ithas crept up high enough to injure the part 4 or the economizer, whichmay take the place of part 4. The same purpose is achieved by themodification shown in Fig. 2. In this case the means for preventing theshortening of the are after the rail (5 has reached its lowermost pointis a short narrow plate 21 secured to the upper side of the rail 6 insuch position, that when the rail has descended to its lowermost pointthis plate 21 will with one of its ends abut against the holder 13 ofthe electrode 11, on the inner side thereof. This positively preventsthe approach of the electrode 11 to the electrode 10 by the action ofthe regulating mechanism upon the bell-crank lever and of the latterupon the plate 5 and electrode 11. Any other means for preventing theelectrodes to approach each other when they have reached the lowestlimit, or any predetermined limit of feeding motion comes within myinvention.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent, is:

1. In an arc lamp with downwardly converging electrodes, means movablewith said electrodes for supporting them and causing them to descend instep with each other, means for moving one of said electrodes laterallytoward the other to compensate for the lengthening of the arc and meanscooperating with said supporting means for preventing said lateralmovement of the movable electrode when a predetermined limit of thedownward feed has been reached.

2. In an arc lamp with downwardly converging electrodes, a downwardlymovable rail for supporting said electrodes, means for moving one ofsaid electrodes laterally toward the other to compensate for thelengthening of the arc, and means carried by said rail for preventingsaid compensating movement when a predetermined limit of the downwardfeed has been reached.

3. In an arc lamp with downwardly converging electrodes, a downwardlymovable rail for supporting said electrodes, means comprising a platethrough which one of said electrodes passes and a lever cooperatingtherewith, for moving said elect-rode laterally toward the other tocompensate for the lengthening of the are and means carried by said railcooperating with said lever for preventing the lateral movement of themovable electrode when a predetermined point of the downward feed hasbeen reached.

In witness whereof, I have hereunto set my hand this 16th day of June.1908.

ALBERT SCHELLENBERGER.

Witnesses JULIUS RUMLAND, KARL h IIoKELsEN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. G.

